<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<link rel="stylesheet" href="../common.css">
<style>
  h1 {
    color: #000;
    font-size: 8em;
    display: flex;
  }

  h1 span {
    animation: animate 1s linear infinite;
  }

  h1 span:nth-child(1) {
    animation-delay: 0;
  }

  h1 span:nth-child(2) {
    animation-delay: 0.1s;
  }

  h1 span:nth-child(3) {
    animation-delay: 0.2s;
  }

  h1 span:nth-child(4) {
    animation-delay: 0.3s;
  }

  h1 span:nth-child(5) {
    animation-delay: 0.4s;
  }

  h1 span:nth-child(6) {
    animation-delay: 0.5s;
  }

  h1 span:nth-child(7) {
    animation-delay: 0.6s;
  }

  h1 span:nth-child(8) {
    animation-delay: 0.7s;
  }

  h1 span:nth-child(9) {
    animation-delay: 0.8s;
  }

  h1 span:nth-child(10) {
    animation-delay: 0.9s;
  }

  @keyframes animate {

    0%,
    100% {
      color: #fff;
      filter: blur(3px);
      text-shadow: 0 0 10px orange,
        0 0 20px orange,
        0 0 40px orange,
        0 0 80px orange,
        0 0 120px orange,
        0 0 240px orange,
        0 0 320px orange,
        0 0 480px orange,
        0 0 600px orange,
        0 0 720px orange;
    }

    25%,
    75% {
      color: #000;
      filter: blur(0);
      text-shadow: none;
    }
  }
</style>

<body>
  <h1>
    <span>S</span>
    <span>u</span>
    <span>S</span>
    <span>u</span>
    <span>i</span>
    <span>s</span>
    <span>s</span>
    <span>u</span>
    <span>s</span>
    <span>u</span>
  </h1>

</body>

</html>